The Australian plate is heading north while the Pacific plate is heading west, and the combination of these motions means that the Pacific plate, which includes much of the South Island, is moving relative to the Australian plate at a rate of about 40millimeterss each year in a southwesterly direction.

“One of the biggest hazards of that kind of earthquake is the tsunami that is triggered by a fault rupture offshore.,” Cochran added. “We know from tsunami modeling from a hypothetical earthquake from the Hikurangi subduction zone that the travel times could be very short to the coast, so seven minutes for some of the south Wairarapa coast.”

One year after it struck, scientists are also warning that the Kaikoura quake was not the “big one” for the Hikurangi subduction zone. The quake on the Hikurangi subduction zone was devastating. The magnitude 7.8 that destroyed houses, lifted the Kaikoura seabed by 2m, tore apart farmland, and wrecked kilometers of State Highway 1, may be minor compared to what could come, Cochran said.